The present invention relates to a water supply device for divers and the device has a push rod threadedly connected to a piston member in a cylinder so that the push rod can be disengaged from the piston member and received in the cylinder when the push rod is not in use.
A conventional water supply device known to applicant is disclosed in U.S. Pat. No. 5,524,612 to Chen with a title of xe2x80x9cDrinking Device For Driversxe2x80x9d, filed Nov., 22, 1994. A mouthpiece is connected to a cylinder which includes a push rod and a cylinder in which water is filled. The push rod can be pushed into the cylinder to squeeze water in the cylinder into the mouthpiece for relief thirsty of the divers. Another water supply device 80 is disclosed in FIG. 8 and has a similar structure as the cylinder in U.S. Pat. No. 5,524,612. The cylinder 81 has a push rod 83 movably inserted therein and a head 831 is connected to the push rod 83 and accessible by the diver. A piston member 85 is mounted to the push rod 83 and located in the cylinder 81. A spring 82 is biased between the piston member 85 and an end of the cylinder 81 so that the piston member 85 is kept at the left extreme position as shown in FIG. 8. When the diver pushes the push rod 83, the piston member 85 pushes the water in the cylinder 81 to flow out from a passage 84 communicating with an interior of the cylinder 81.
Both of the conventional water supply devices shown above involve a push rod that extends outward from the cylinder 81. However, the extending push rod sometimes is not convenient for the divers especially when diving in a narrow space because the push rod could be tangled by objects around the divers.
The present invention intends to provide a water supply device for divers wherein the push rod can be received in the cylinder when it is not to be used.
In accordance with one aspect of the present invention, there is provided a water supply device and comprising a cylinder connected to a mouthpiece which has a passage communicating with an interior of the cylinder. An inlet is defined radially through the cylinder and a pipe is connected between the inlet and a bladder. A piston member is received in the cylinder and has a central passage defined longitudinally therethrough. A threaded portion is defined in a periphery defining the central passage and a spring is biased between the piston member and a closed end of the cylinder. A push rod extends through the central passage of the piston member and has a threaded section engaged with the threaded portion of the piston member. The push rod can be disengaged from the threaded portion of the piston member and received in the cylinder.
The primary object of the present invention is to provide a water supply device for divers wherein the push rod of the device can be received in the cylinder so that the push rod will not tangle objects.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.